Impact of sex differences and network systems on the in-hospital mortality of patients with ST-segment elevation acute myocardial infarction.

Introduction And Objectives: Network systems have achieved reductions in both time to reperfusion and in-hospital mortality in patients with ST-segment elevation myocardial infarction (STEMI). However, the data have not been disaggregated by sex. The aim of this study was to analyze the influence of network systems on sex differences in primary percutaneous coronary intervention (pPCI) and in-hospital mortality from 2005 to 2015.

Methods: The Minimum Data Set of the Spanish National Health System was used to identify patients with STEMI. Logistic multilevel regression models and Poisson regression analysis were used to calculate risk-standardized in-hospital mortality ratios and incidence rate ratios (IRRs).

Results: Of 324 998 STEMI patients, 277 281 were selected after exclusions (29% women). Even when STEMI networks were established, the use of reperfusion therapy (PCI, fibrinolysis, and CABG) was lower in women than in men from 2005 to 2015: 56.6% vs 75.6% in men and 36.4% vs 57.0% in women, respectively (both P<.001). pPCI use increased from 34.9% to 68.1% in men (IRR, 1.07) and from 21.7% to 51.7% in women (IRR, 1.08). The crude in-hospital mortality rate was higher in women (9.3% vs 18.7%; P<.001) but decreased from 2005 to 2015 (IRRs, 0.97 for men and 0.98 for women; both P < .001). Female sex was an independent risk factor for mortality (adjusted OR, 1.23; P<.001). The risk-standardized in-hospital mortality ratio was lower in women when STEMI networks were in place (16.9% vs 19.1%, P<.001). pPCI and the presence of STEMI networks were associated with lower in-hospital mortality in women (adjusted ORs, 0.30 and 0.75, respectively; both P<.001).

Conclusions: Women were less likely to receive pPCI and had higher in-hospital mortality than men throughout the 11-year study period, even with the presence of a network system for STEMI.